BEIJING, March 21 (Xinhua) -- North China's Hebei Province, the major water supplier to Beijing, has overexploited its groundwater which caused subsidence and formed "20 hopper areas" of more than 40,000 square km, said a local water conservancy official on Saturday.

    "Water shortage has become a big problem facing the province's social and economic development," Li Qinglin, director of Hebei's water conservancy department, told a forum marking the 17th World Water Day which falls on Sunday.

    "Water resources in Hebei have dwindled by nearly 50 percent in recent years compared with that in the 1950s," said Li, adding the province consumes 20.5 billion to 21.5 billion cubic meters water annually but it has only 17 billion cubic meters of surface water, leaving groundwater to supply the margin.

    A water conservancy expert earlier said Hebei has overused 120 billion cubic meters of groundwater in 30 years since 1976.

    The expert who declined to be named estimated that the average per capita water resources in Hebei was only one-seventh of the national average.

    Southwestern Chongqing Municipality has a relatively better prospect, which sees its average per capita water two-thirds of the national average, according to local government statistics.

    Chongqing has 1,802 cubic meters of water per person.

    While meeting its own needs, Hebei Province supplies water to neighboring Beijing and Tianjin, where three big reservoirs are backed by water from Hebei.

    Li urged the government to take measures to reduce water consumption for the sake of sustainable economic and social development."